Colour settings in Windows 10?

[mark_a_scott]

I notice that Windows 10 references "32bit colour", however each RGB channel can take a value of 0-255 which is 8 bits a channel which is a total of 24 bits. Where have the other 8 bits gone?

[kalniel]

I notice that Windows 10 references "32bit colour", however each RGB channel can take a value of 0-255 which is 8 bits a channel which is a total of 24 bits. Where have the other 8 bits gone?

alpha/transparency.